Unable to create clusters with more than 200 nodes

[golharam]

When doing so, StarCluster submits the request to AWS, and that part is successful. When StarCluster then queries for the state of the nodes, AWS complains and says "Cannot query for more than 200 instances" at a time. At this point StarCluster thinks the cluster creation process fails. StarCluster needs to be updated to query for 200 or less instances at a time.

[vasisht]

See #434

This is implemented in the vanilla_improvements branch at https://github.com/datacratic/StarCluster